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.Dd February 14, 2024
.Dt ZPOOL-PREFETCH 8
.Os
.
.Sh NAME
.Nm zpool-prefetch
.Nd Prefetches pool metadata into ARC
.Sh SYNOPSIS
.Nm zpool
.Cm prefetch
.Op Fl t Ar type
.Ar pool
.Sh DESCRIPTION
Massively prefetch metadata of a specific type for the given pool into the ARC
to reduce latency of some operations later.
If no type is specified, all types are prefetched.
.Pp
The following types are supported:
.Bl -tag -width "brt"
.It Sy brt
Prefetch the BRT (block reference table).
This may improve performance for block cloning operations,
and frees for earlier cloned blocks.
.It Sy ddt
Prefetch the DDT (deduplication table).
This may improve performance of writes when deduplication is enabled,
and frees for earlier deduplicated blocks.
.El
